Well, I don't know what else to say. I've even used it on brand new parts like the tubular A-arms on the Muskrat II. Just scuffed them up with 120, wiped them dowm with denatured alcohol, POR-15, let flash, sprayed on some Marhyde self-etching primer, then the color coat. Still on there after 3 years.
Sandblasting can still be used. You don't need to take all the rust off, just the scale and "skin" that develops over time. For me it saves time, as I don't have to physically work around odd shapes, rivets, etc...
For those of you with negative results, I would ask what was done between the sandblasting and the POR-15, and was it topcoated? brushed on or sprayed? I generally use the "clear" and I only use enough to get full coverage. Always brushed on. I have never used any kind of Metal Prep or Wash of any kind, other than wiping down with thinner or alcohol.
I never meant to imply that it doesn't work over rust. I use it "as intended" most of the time. I guess I just prefer to get things as clean as possible, and I use the POR-15 as "insurance" against future rust. Apparently I'm a luckier person than I thought.
